When rebuilding my carb I took the slide or piston, whatever you want to call it, out of the top of the carb. I went to change the needle jet but relized that the previous owner had changed it and moved the clip 1 slot down. So I went to put it back together but forgot if the holder covered the top hole, which you can see in the picture. If this whole is spose to be covered by that holder than I think this may be why my blaster wont start. Thanks